Roller skate



FIG. 1 is a side elevational view of one side of a roller skate illustrating our new design, the other side appearing substantially a mirror image of the side shown;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevational view thereof; and

FIG. 4 is a front elevational view thereof. 

The ornamental design for a roller skate, as shown and described. 